Penn researchers propose faster computer

Metamaterials could be incorporated into analog computers to perform specific operations

Put down your smart phone. The next big thing in computer science is analog computing.

If you are wondering why anyone would want to resurrect a computing system synonymous with dinosaurs in the age of widespread digital technology, you are not alone.

However, electrical and systems engineering professor Nader Engheta and his team of researchers believe that analog computers, when coupled with metamaterials, which can bend light around materials, have a place in the digital world.

While analog computers are unlikely to replace your Macbook Pro, they may improve your camera. Digital computing thrives because of its highly programmable and multipurpose nature. Analog computing can be used to perform specific operations, such as pattern recognition and image processing, like in cameras.

“Analog computing has its own niche,” Engheta said.

Furthermore, metamaterials have the potential to make bulky analog machines much more compact, efficient and workable. Analog and digital computers’ electricity currently operates on a microwave radio frequency. With the implementation of metamaterials, they can run on a faster, more energy-efficient optical frequency.

This concept, known as metatronics, essentially mimics the way that electricity operates, but on a higher (and therefore faster) frequency such as optical frequencies.

“This research can lead to new devices and applications that were unthinkable a couple of years before,” Alexandre Alves da Silva, a researcher in Engheta’s group, said in an email.

Since metamaterials are manmade, they “give us responses and behaviors that we cannot find in nature,” third-year doctoral student Ahmed Mahmoud said.

The basic structure of these materials involves a collection of smaller objects embedded into a larger host material. Researchers are able to manipulate the composition of both of these components, as well as their density, arrangement and overall shape of the structure. The flexibility of these various components allows for the wide range of applications of this technology.

Because they are specifically engineered for their particular applications, metamaterials can be designed for particular purposes and move computer engineering forward.

“Metamaterials is the field where you rethink the whole idea of all devices,” Mahmoud said. “People were always limited because they think we only have the materials in nature.”

“Meta, in Greek, means ‘beyond,’” Engheta added.

Metamaterials can also be used to make objects invisible.This involves the engineered material to cover the surface of another (small) material such that the wave will pass around the object without scattering, Engheta said.

“As engineers, we want to change things,” third-year doctoral student Fereshteh Abbasi, who also works in Engheta’s research group, said. “We cannot accept any limits. Metamaterials fight the limits of nature.”